Press



April 21, 1959 e. P. M. BERNIER PRESS 3 Sheets-Sheet 1 Filed March 12,1956 .l I I MN g mm .|l|l|l||v ll] a 1 4 n N 1 3 KM Q. m :1 Nm %N 3 mmmm April 21, 1959 G. P. M. BERNIER PRESS 3 Sheets-Sheet 2 Filed March12, 1956 Ill l Q Q April 21,1959 G. P. M. BERNIER PRESS 3 Sheets-Sheet 3Filed March 12, 1956 PRESS Gaston Pierre Marie Bernier,Chalonnes-sur-Loire, France, assignor to Constructions Meca-MetalliquesChalonnaises, Chalonnes-sur-Loire (Maine-et-Loire), France, acorporation of France Application March 1-2, 1956, Serial No. 571,055Claims priority, application France March 16, 1955 5 Claims. (Cl. 100.-.-52)

The present invention relates to presses intended for expressing juicesand other liquids from various products, such as grapesyapples, pears,and the like, which is of the type comprising. a screen formed by a sortof barrel which is mounted to rotate about a horizontal axis and insidewhich is placed the fruit or other product to be pressed, while thejuice or other liquids flow through the free longitudinal gaps leftbetween the bars of the screen.

For pressing the product contained in the screen, various solutions havealready been proposed. One solution is to provide two. keyed plateswhich are coaxial with the screen and are slidable in relation to thelatter, these plates forming nuts engaged on two oppositely directedscrew threads formed on a fixed screw, so that by rotation of the screenin one direction the plates are brought nearer to one another, whilethey move apart on rotation of the screen in the other direction.

The product to be pressed is accommodated between the two plates and istherefore compressed axially in proportion as the plates move towardsone another. Experience shows that this arrangement does not enableuniform pressure to be applied in the interior of the compressedproduct, and this pressure, which is particularly great near the plates,decreases progressively from the plates towards the median plane of thespace therebetween and from the periphery of the screen towards thecentre. The result is usually that the juices or other liquids arecompletely extracted only after a very long period of operation.

Another solution is to provide a screen having two fixed ends anddisposing in said screen, coaxially thereto, an expansible hollow bodywhich is inflated by the introduet'on of air under pressure.

.In this case the product to be expressed is compressed in thecentrifugal radial direction between the expansible body and the screen,in the form of an annular mass which, in the case (If most products,very quickly be comes, compact, while itsperrneability declines to suchan extent that the liquid soon becomes very diflicult to express. 7

The. object of the present invention is to provide apress of the typecomprising a rotating screen and two plates moving in oppositedirections on a fixed axial crew n which said pla w h are a ly y drelative to the screen, form nuts, said press being characterised inthat there is disposed between said plates and around the screw ahydraulic core of constant volume but deformable, and whichisconstituted by a fluid-tight chamber ofannularcross-sectionsurrounding the screw' and filled with a liquid, that is a fluid butincompressible product.

in one embodiment, the fiuidvtight wall of this chamher is formed .bythe combination of atubular sleeve, of rubber or like-elastic,deformablematerial, and two end. pieces on which said sleeve is fixed tobe fluid-tight, said end pieces forming fluid-tight nuts .on the screwand i df jjf' j; at

2,882,815 Patented Apr. 21, 1959 being rigid with the two movable platesin respect of rotational and longitudinal displacements of the latter.

As a result of this arrangement, when the two plates move towards oneanother, the shape of the chamber, and consequently the hydraulic core,changes without its volume altering. This chamber, which has acylindrical shape when the plates are moved apart to the maximum extent,assumes the shape of a truncated double cone, while its elastic wallcontracts to adapt its length to the new shape. As a result of thebroadened shape of the chamber when the two plates move towards oneanother, it will be found that the pressure inside the product expressedis distributed much better and that the flow of the liquid towards thescreen is no longer obstructed.

When the plates are moved apart between the successive stages ofexpressing the product, the hydraulic core always resumes its initialelongated shape, without any variation in volume, thus promoting thebreaking up of the cake formed for the following expressing stage.

According to another feature of the invention, the fluid-tight chamberis connected to a closed chamber by a movable member connected to a pushmember which controls a switch controlling the circuit of the drivingmotor of the rotating screen, for the purpose of opening the supplycircuit of said motor when the pressure of the liquid contained in theconstant volume chamber attains a given value and closing it when thepressure falls to a predetermined lower value.

When the product to be expressed is readily pressed, the fluid-tightconstant volume chamber may be provided only for the purpose ofcontrolling the switch and in this case said chamber may be of verysmall volume.

Other features will be clear from the description hereinbelow.

In the accompanying drawing, which is given solely by way of example:

Fig. l is an elevational view, on a small scale, of a press embodyingthe invention;

Fig. 2 is an end view thereof;

Fig. 3 is a longitudinal sectional view thereof, on an enlarged scale;

Fig. 4 is a detail view showing the method of anchoring the screw in thesupporting frame;

Fig. 5 is a view similar to Fig. 3 of the position assumed by the movingparts at the end of an expressing operation;

Fig. 6 is a sectionalview, on an enlarged scale, of the connection tothe hub of one of the two moving plates of the adjacent end piece of thechamber forming the hydraulic core of constant volume;

Fig. 7 is a partial longitudinal sectional view of a first modificationin which the press is stopped automatically when a certain pressure hasbeen obtained in said press, and

Fig. 8 is a similar view of a second modification.

The embodiment of the invention shown in Figs. 1 to 6 relates to a pressof known type comprising a structure formed by a frame having twolongitudinal members 1 and two cross-members 2 and carried by legs 3.

Fixed to the two cross-members 2 by two flat faces 4 is an axial screw 5whose end portions, provided with these flat faces, are anchored in abearing having two parts 6 and 7 which are fastened on the correspondingcross-member 2 (see Figs. 2, 3 and 4.). The screw 5, whose axiscoincides with the horizontal axis XX of the press, has .twoscrew-threaded portions 5 and 5 the screw-threads of which areoppositely directed. These portionsterminate at a certain distance fromthe anchoringjfiat faces 4 so as ,to create two cylindrical journals 8on each of which is rotatable a hub 9 connected by radial arms 10 to aring 11. The two rings 11 are provided with an outer toothing 12 andform with the slats 13 a barrel-shaped-screen, which rotates about theaxis XX. The slats 13 are spaced slightly apart to enable juices orother liquids resulting from expressing to flow freely therebetween.

The slats 13 are held by hoops 14. Furthermore,

the two rings 11 are tied by rods 15 which are housed inside the screen,the latter being inserted in the rings each of which are provided forthis purpose with a recess 15. The screen is provided with a fillinghole having a door 16 (see Fig. l).

The rotating assembly constituted by the two rings and the screen isrotated about the axis XX alternately in one direction and then theother, by a reversible electric motor 17 (Fig. 2) the supply circuit ofwhich is controlled by a reversing switch. The shaft18 of said motordrives a pulley 20 keyed to a longitudinal shaft 21, through the mediumof a belt 19 (Fig. 2). Two pinions 22 (Figs. 1 and 2) are keyed to saidshaft 21 and mesh with the toothing 12 of the rings 11 of the screen.

Slidably keyed in the screen by the ties 15, are two transverse plates23 each of which is movable longitudinally and connected by Welding orsome other manner to a sleeve 24 which is rigid with a hub 25, thelatter being screw-threaded at 26 (Figs. 3 and 6), so as to form a nutengaged on the corresponding screwed portion 5 or 5 of the fixed axialscrew 5.

It will be seen that depending upon the direction of rotation of thescreen the plates and the nuts turn in one direction or the other on thescrew, thus obtaining a translatory movement of said plates eithertowards one another from the position shown in Fig. 3 to that shown inFig. 5, or a movement in the opposite direction.

The assembly of known type described hereinabove is completed in thefollowing way according to the invention. Mounted on the two portions 5and 5 of the screw in the manner of two auxiliary nuts, are two endpieces 27 of rubber or similar material, which clamp elastically overthe threaded portions of the screw with which they form a joint whileserving as supports for a sleeve 28. Said sleeve 28 of rubber or likedeformable and elastic material is cylindrical, of circular section,when it is elongated under longitudinal tension (the position shown inFig. 2). Its two ends are fixed in a fluid-tight manner on the endpieces 27. Each of said end pieces preferably comprises on the sleeveside thereof, as shown in Fig. 6, a shoulder of greater diameter thanthe rest of the end piece, the sleeve being fastened beyond saidshoulder on the smaller cylindrical part of the end piece by means of aclamping ring 28.

The smaller cylindrical part of each end piece is fitted and fastened,for example by vulcanization, inside a metal sleeve 29 which extendsbeyond the end piece. In the part thereof not covering the end piecesaid sleeve is provided with holes 30. The free end of the sleeve isconnected, for example by welding, at 31 (Fig. 6), to the sleeve 24 ofthe hub of the corresponding plate 23, so that said sleeve and the endpiece 27 participate in the longitudinal movements of the hub of theplate and, in consequence, of said plate along the screw 5.

When the press is in the position shown in Fig. 3, with the two platesmoved apart to the maximum ex tent, the sleeve 28, which is underelastic tension, determines between the two end pieces 27 and around thescrew 5 an annular chamber of circular section having a certain volume(V). This chamber is filled with a liquid 32 which can be, for example,water or jack oil or any other liquid of the same nature as that whichthe press is intended to extract from the products to be expressed.

The machine operates in the following manner:

When the'machine is in the position shown in Fig. 3

and the door 16 (Fig. l) is removed (or opened), the annular spacebetween the two plates 23, which are separated, and the sleeve 28 isfilled with the fruit (grapes, apples, pears, etc.) which is to beexpressed. The door 16 is then replaced (or closed) and the motor 17started so that the rotor assembly, constituted by the screen, theplates 23 with their hubs 24, the end pieces 27 and the sleeve 28, turnsin relation to the screw in the direction of the arrow f (Fig. 3).

In consequence of this rotation and of the directions of inclination ofthe screw-threaded portions 5 and 5 of the fixed screw 5, the hubs 24,operating as nuts, travel along said portions towards one another, andthe same applies of course to the plates 23 which compress the fruitbetween them while the end pieces 27, connected to the nuts 25 by thesleeves 29, participate in the rotation of said nuts and move towardsone another at the same speed as the nuts.

There is thus a decrease in the length of the chamber created by thesleeve 28, and as the volume (V) of the chamber is at the outset filledwith liquid 32, the moving together of the end pieces 27 is manifestedin a deformation of the sleeve 28, which gradually assumes the shape ofa double truncated cone shown at 28 in Fig. 5, this shape being suchthat the developed length of the sleeve decreases, said sleevecontracting longitudinally while increasing in cross-sectional size, thevolume there of retaining the initial value (V). The sleeve thereforeremains full of liquid.

Owing to the shape of a truncated double cone assumed at 28 by thehydraulic core constituted by the sleeve and its liquid contents, itwill be immediately seen that the fruit disposed around this core in thefree space in the screen between the two plates 23, has a thickness inthe axial direction of the screen which increases from the axis towardsthe periphery of the screen.

As pressing progresses, the particles of the expressed material areprogressively deflected outwardly, while the liquid flows in thedirection indicated by the arrows. In fact, the two parts of the cakeformed on either side of the core between the two plates 23 are eachcompressed between the transverse face of the corresponding plate 23 andthe slanting face of the truncated cone of the central hydraulic core,that is under conditions which are a compromise between the axialpressing obtained in the known type of machines in which the plates aremoved towards one another and the radial centrifugal pressing obtainedin machines having fixed plates and an expansible chamber.

In comparison with this expansible chamber, it will be seen that thehydraulic core has a constant volume and is not expansible, the sleeve28 on the contrary contracting in the longitudinal direction, passingfrom the position shown in Fig. 3 before expressing to that shown inFig. 5 at the end of compression.

Briefly, on account of the position assumed by the hydraulic core inFig. 5, the liquid may be completely expressed in a much more rapidmanner and with less trituration of the expressed product which, by thisvery fact, breaks up less than in either of the two known types ofmachines. In fact, in comparison with the first type, the pressure ismuch better distributed inside the two parts of the cake containedbetween the hydraulic core and the plates, while there is completefreedom for the liquid to travel towards the periphery, where thecompression is substantially lower, since the pressure decreases fromthe axis towards the periphery of the screen, thus facilitating theevacuation of the liquid. Moreover, in comparison with the machineshaving an expansible chamber, the formation of a shell of a more or lessimpermeable compressed product against the slats of the screen isprevented, and the crumbling of the cake is time and facilitatingdraining.

When the moving assembly has reached to the position shown in Fig. 5,which is substantially anextreme position, the direction of rotation ofthe motor is reversed, t P at s m re apart ant ere a ti of th i nu 24,and the latter, by their connections 29 to the end pieces 27, pull onsaid end pieces which follow the movement, returning to thepositionshown in Fig. 3. This operation, which corresponds to a decompression'ofthe hollow cake formed, enables said cake to be broken up, the cakebeing no longer supported by the sleeve, which passes from the position28 to the rectilinear position 28 shown in Fig. 3.

As soon as the position shown in Fig. 3 is resumed, the movement in theopposite direction is recommenced, and so on for a number of times untilall the liquid contained in the product is expressed.

This liquid naturally flows through the slats of the screen, thereaftertrickling onto an inclined floor supporting the frame 3 which is theusual arrangement. Alternatively, the liquid is received in a containerdisposed beneath the press and serving as a support therefor.

It will be seen that during the expressing operation, part of the liquidmay come into immediate contact, through the orifices in the sleeves 29,with the screw in the region of its threaded portions 5 and 5 Thisliquid thus reaches, through the roots of the screw-threads, the insideof the bore of the nuts 25, and flows through said bores which are thussufiiciently lubricated by this liquid without need for any otherlubricant.

Fig. 7 shows a first modification in which the presence of the liquid 32inside the sleeve 28 is used to advantage to control the supply of powerto the driving motor 17 of the press rotor.

To this end, there is disposed in the supply circuit 32 for the motorbetween the latter and a reversing switch 33 of any type, a switch 34which is opened by a push member 35 combined in the known manner withregulating means (not shown) which, for a given force on the pushmember, permit regulation of the instant of disconnection and automaticreconnection when the evacuation of the juices contained in the cake hassufliciently reduced the pressure exerted on said push member.

According to the invention, said push member 35 bears, by its head,against a diaphragm 36 which constitutes a deformable wall of a chamber37, formed by a block 38 connected to the case 39 of the switch 34. Saidchamber 3''? is connected by a connection 40 to an axial passageprovided in the screw 5 and communicating through a median radial hole42 with the chamber formed by the sleeve 28.

As will be seen, when the two plates 23 of the press are broughttogether, the pressure exerted by the com pressed product on said sleeve28 and the liquid 32 contained therein increases the pressure of saidliquid and 1 this pressure is transmitted, without substantial volumevariation, to the chamber 37 where it acts upon the push member 35through the medium of the diaphragm 36. A pressure gauge 43 can beconnected to this chamber 37 to check the operating pressure.

As soon as the pressure reaches a given value, which may be adjustableby usual means for regulating the switch 34, said switch opens thecircuit of the motor 17 and stops the operation.

When the pressure has fallen owing to part of the juice flowing from thecake, the circuit of the motor 17 automatically closes by the reverseoperation of the switch, until the disconnecting pressure is againreached, and so on.

By reversing the reversing switch 33, the direction of supply of themotor is reversed and the plates are moved apart, and the expressingoperation can be recommenced if necessary, this being done as many timesas necessary.

Another modification is shown in Fig. 8, in which the fluid tightconstant. volume chamber is of greatly redimensions and is intendedsolely to eifect a'utomatic opera on of the switch inaccordancewitlitli'e' ex pressing pressure. According to this statesm n; the fluitightf chamber, is forined' on the central non-threaded por I '44 of theaxial screw 5 the combination of two Iings' l S and 4 6,"'whicli are"fixed in' 'a" fluid-tight manner finjsaid portion 44, 'ancla shorthovering 47 6f rubber orlike elastic" material, which is damped in afluid-tight manner on said rings by two clamping' riiigs 48 and 49.

As in the first example, the interior of the chamber thus formed isconnected by the radial hole 42 and the axial passage 41 to the chamber37 closed by the diaphragm 36, which actuates the push member 35controlling the switch 34 controlling the power supply to the motor 17.

Although specific embodiments of the invention have been described, manychanges and modifications may be made therein without departing from thescope of the invention as defined in the appended claims.

It will be seen that if necessary there may be disposed in the spacewhich receives the product to be expressed, a conventional device whichhas break-up chains and hoops and is intended to dislocate the more orless compact cakes obtained at the end of each compression period.

Having now described my invention what I claim as new and desire tosecure by Letters Patent is:

1. A press for extracting a liquid from a product to be pressed, saidpress comprising a frame, an axial horizontal screw fixedly mounted insaid frame and having two oppositely screw-threaded portions and twosmooth end portions, a horizontally disposed cylindrical screenrotatably mounted on said smooth portions of said screw, anelectromechanical device for rotationally driving said screen about theaxis of said screw, two plates slidably keyed in said screen, saidplates including first nuts screw-threadedly mounted on saidscrewthreaded portions of said screw, and a deformable core of constantvolume disposed around said screw between said plates, said core beingdefined by two end pieces which form fluid-tight second nuts on saidscrew and an interposed tubular sleeve of elastic deformable materialfixed in a fluid-tight manner on said end pieces to define an annularchamber around said screw and a liquid continuously confined in andfilling said annular chamber, and connecting means connecting said endpieces to said plates for rotational movement with said plates whilemaintaining said end pieces axially spaced from said plates in adirection parallel with said screw, whereby when said plates are movedtoward one another upon rotation of said screen said sleeve assumessubstantially the form of a truncated double cone which is urgedradially into the product to be pressed and facilitates the pressing ofsaid product, said annular space within said sleeve varying in shape butremaining unvaried in volume throughout the cycle of operation of thepress.

2. A press as claimed in claim 1, wherein said plates have hubs whichform said first nuts and said connecting means are formed by sleevesconnecting said end pieces to said hubs, said sleeves being providedwith holes to permit the liquid extracted from the product being pressedto lubricate said first nuts.

3. A press as claimed in claim 1, further comprising an electric powersupply circuit for said electromechanical device, an electric switchdisposed in said electric power supply circuit, a hydraulic device foractuating said switch, and a passageway provided in said screw andconnecting said hydraulic device to the inside of said sleeve wherebysaid switch is opened and said electromechanical device ceases tooperate when a given pressure prevails in said core and said switch isonce more closed when a pressure lower than said given pressure prevailsin said core.

. 7 i l 4. A press as claimed in claim 3, wherein said hydraulic devicecomprises a chamber closed by a movable member connected to a pushmember operatively connected to the switch, said chamber being connectedby said passageway to said annular chamber of said core.

5. A press as defined in claim 1 further comprising means for actuatingsaid electromechanical device in response to variations in the pressureof said liquid in said chamber.

References Cited in the file of this patent UNITED STATES PATENTSWhittington Aug. 3, 1954 FOREIGN PATENTS France Dec. 23, 1953 France May6, 1954

